In the present description and the following claims, with the generic term “deambulation” it is intended the act of walking or running carried out by a person, while with the generic term “sole”, it is intended the portion of the shoe comprising the outsole and the insole of the shoe itself.
In the state of the art so-called “energy harvesters” (in brief, EH) are known, which are able to store the available energy in one environment in order to render it directly usable. One example known to all is represented by photovoltaic cells, which store solar energy in order to convert it into directly-usable energy, for example, for the operation of a calculator or a watch or other electronic devices.
The energy harvesters available in the art are of different type according to the specific application; in the footwear field, an energy harvester has been recently proposed that is capable of storing the energy generated during deambulation in the form of pressure variations exerted by a foot on the shoe sole, in order to render such energy directly available for use.
A harvester of this type has for example been proposed by the U.S. company InStep Nanopower.
One such harvester is activated by a respective actuator group in response to the pressure variations exerted by the foot on the sole during deambulation. The actuator group comprises a fluid-dynamic circuit connected to the ends of the harvester.
Presently, however, one such harvester only allows storing a minimum part of the energy produced during deambulation, with the result that the quantity of energy recovered by the harvester is not actually sufficient for allowing, for example, the power supply of electronic devices directly or remotely connected to the harvester itself.
This is due to different factors. First, to the fact that the fluid-dynamic circuit, as it is configured, is unable to operate on the energy harvester in such a manner to allow it to convert a sufficient quantity of energy produced during deambulation into electrical energy.
It follows that the electrical energy produced by the harvester and accumulated by suitable accumulating/dispensing means is not sufficient for the power supply of electronic devices even operating with very limited powers, on the order of a few mWatt, up to 1-2 Watt.
There is therefore the need to provide a sole for footwear capable of recovering energy produced during deambulation in a more efficient manner with respect to the conventional soles of this type.
There is also the need to provide a sole for footwear capable of recovering part of the energy produced during deambulation having an alternative configuration with respect to those proposed up to now.